The twelfth century witnessed an impressive production of scientific treatises in Hebrew, which were the result of the close interaction of Jewish culture with Arabic culture in Muslim territories and the role of Jews in Muslim and Christian courts. Often, Jews were also intermediaries in the intensive transfer of knowledge from Arabic into Latin that most notably took place in the Iberian Peninsula, especially in the twelfth and thirteenth centuries. As a result of this close contact with Arabic culture, the Hebrew language underwent a process of specialization which saw the creation of many new technical terms. Bar Hiyya's decision introduced a radical change in Hebrew literature and science: the Hebrew language had to be enhanced to accommodate the new knowledge introduced in Arabic, for there were no words for all the new scientific concepts and calculations. The Hebrew language had been developed and expanded mainly in the fields of religion and poetry.